CN1171134C - Equipment and method of preventing overcurrent from resulting in system stop - Google Patents
Equipment and method of preventing overcurrent from resulting in system stop Download PDFInfo
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- CN1171134C CN1171134C CNB001018108A CN00101810A CN1171134C CN 1171134 C CN1171134 C CN 1171134C CN B001018108 A CNB001018108 A CN B001018108A CN 00101810 A CN00101810 A CN 00101810A CN 1171134 C CN1171134 C CN 1171134C
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Abstract
The present invention relates to a device and a method for preventing excess currents for resulting in system shutdown. The method comprises the steps: firstly, a current sensing circuit is used for sensing load currents flowing through a system power supply path, and the load currents are converted into the corresponding load voltage; a shutdown control device of peripheral devices determines the peripheral devices in the system, which need to be shut down, according to the load voltage and the corresponding excess current extent; then, the shutdown signals corresponding to the peripheral devices are generated, and the peripheral devices needing to shut down are shut down in a proper drive mode. Thus, the whole electric power requirement of the system is reduced, and the load currents are reduced. Thereby, the condition that system shutdown is caused by the excess currents can be prevented.
Description
Technical field
The present invention relates to a kind of power control and method, prevent that particularly General System (for example computer system) from causing the apparatus and method of system-down because of excess current, use the shutdown of avoiding system burst and the damage that causes partial information.
Background technology
The situation of excess current may take place in general electronic system under the operating environment of some overload.When having served as current phenomena and occurring, system just may be because of can't normal running and shut down rapidly.The electronic component of part is damaged in undesired sudden shutdown so possibly, and in computer system, also can destroy the information in storer or the storage cryopreservation device (for example Winchester disk drive).Therefore, general electronic system must avoid taking place the situation of above-mentioned excess current as far as possible.
Known technology mostly is to adopt the mode that limits load current to avoid the generation of excess current, yet this mode is also incorrect on actual treatment.For the electronic system in the running, restriction load current meaning work does not have the required electric power of supply system fully.Though might avoid the situation of unexpected shutdown, can't guarantee that also the operation of system is normal simultaneously, obviously doing like this is not optimal solution.
Summary of the invention
In view of this; fundamental purpose of the present invention is to provide a kind of apparatus and method that prevent overcurrent from resulting in system stop; to solve the problem that excess current may cause unexpected shutdown effectively, the system that still can guarantee simultaneously can proceed operation under the normal running environment.
According to above-mentioned purpose, the present invention proposes a kind of device that prevents overcurrent from resulting in system stop.Comprise a core main control part and a plurality of periphery in this system, and provide electrical power to this system through a supply path by power supply.This prevents that overcurrent device from comprising a current sensing circuit and peripheral control circuit.Current sensing circuit is used for detecting the load current on the supply path near supply path, and produces the load voltage corresponding to load current.Peripheral control circuit is judged the excess current degree of load current then according to this load voltage value, and according to the excess current degree of load current, produces the shutdown signal corresponding to required device of closing in the periphery, uses the periphery of closed portion.By this, the needed electric power of total system just can reduce, thereby has avoided the problem of overcurrent from resulting in system stop.
Wherein, peripheral control circuit can be a microcontroller, is made of independent circuits.For example, contain the system circuit in addition and can comprise a bleeder circuit, be coupled to current sensing circuit and place load voltage and an end-point voltage (for example earth terminal) between, in order to produce a plurality of comparative voltages between load voltage and end-point voltage; And a plurality of comparator circuits, respectively a comparative voltage and a reference voltage are compared, in order to the excess current degree of decision load current, produce shutdown signal corresponding to periphery.In addition, contain the system circuit in addition and also can comprise a bleeder circuit, be coupled between a reference voltage and the end-point voltage, in order to produce a plurality of reference comparison voltages between reference voltage and end-point voltage; And a plurality of comparator circuits, respectively reference comparison voltages and load voltage are compared, in order to the excess current degree of decision load current, produce shutdown signal corresponding to periphery.
The present invention also provides a kind of method that prevents overcurrent from resulting in system stop, and it comprises the following steps: at first, and the load current that is flow through on the sensing supply path is changed this load current again and is corresponding load voltage.According to load voltage with and the excess current degree of corresponding load current, produce shutdown signal corresponding to required device of closing in the periphery.At last, utilize this shutdown signal to close required device of closing in the periphery.
Description of drawings
For above-mentioned purpose of the present invention, feature and advantage can be become apparent, a preferred embodiment cited below particularly, and conjunction with figs. elaborates.Wherein:
Fig. 1 represents to prevent in the embodiment of the invention block scheme of the device of overcurrent from resulting in system stop.
Fig. 2 represents to prevent in the embodiment of the invention in the device of overcurrent from resulting in system stop, utilizes the detailed circuit diagram under bleeder circuit and the comparator circuit realization peripheral unit closing control circuit situation.
Fig. 3 represents to prevent in the embodiment of the invention in the device of overcurrent from resulting in system stop, utilizes the control flow chart under the microcontroller realization peripheral unit closing control circuit situation.
Fig. 4 represents to prevent in the embodiment of the invention overcurrent from resulting in system stop method flow diagram.
Embodiment
The disclosed device that prevents overcurrent from resulting in system stop mainly is when overcurrent situations takes place, and comes the electric power of cut-off parts peripheral unit according to the degree of excess current, so that reduce the load current of system, alleviates the degree of excess current.On the other hand, the core of system is then unaffected, therefore still can correctly operate.In the present invention, the peripheral unit that is cut off electric power is to decide according to its importance for System Operation in proper order.Below with an embodiment the present invention is described.
Fig. 1 represents to prevent in the present embodiment block scheme of overcurrent from resulting in system stop device.Comprise core main control part and a plurality of peripheral unit in this system load, and provide electrical power to this system through a supply path by power supply 1.10～1n then represent can cut off in this system electric power peripheral unit A, peripheral unit B, peripheral unit C ..., peripheral unit N.This prevents that excess current from causing the device of shutdown then to be made of current sensor 2, amplifier 3 and peripheral unit closing control circuit 4.Current sensor 2 and amplifier 3 constitute a current sensing circuit, are used for detecting the load current on the supply path, and produce the load voltage corresponding to load current.Wherein, current sensor 2 is near supply path, direct sensing flows through the load current on the supply path, the mode of sensing can adopt dividing technology (utilizing high impedance branch current sense load current) or induction technology (for example utilizing the winding around induction), and current sensor 2 can be converted to load current the voltage form that is suitable for handling (i.e. Dui Ying load voltage value, it is different with the magnitude of voltage in the general so-called load).3 in amplifier is used for received load voltage value is amplified.Load voltage value after 4 of peripheral unit closing control circuits amplify according to this, judge the excess current degree of load current, and according to the excess current degree of load current, make and to close which peripheral unit, so that can reduce in load current to a zone of reasonableness that power supply supplies.Therefore, peripheral unit closing control circuit 4 can produce the shutdown signal of the peripheral unit that need close, closes these peripheral units by this.Therefore, the needed electric power of total system just can reduce, thereby has avoided the problem of overcurrent from resulting in system stop.
When peripheral unit closing control circuit 4 was closed peripheral unit according to the degree of excess current, effect and function that meeting is played the part of in System Operation according to each peripheral unit decided the order that each peripheral unit is closed.In practical application, the setting means of peripheral unit closing sequence is relevant with the characteristic of peripheral unit closing control circuit 4 in the present embodiment.Detailed speech, if peripheral unit closing control circuit 4 is to be made of fixing independent circuits, the requirement in the time of then must be in advance according to System Operation determines the closing sequence of each peripheral unit.For example in Fig. 1, when peripheral unit closing control circuit 4 is checked out the slightest overcurrent situations, can only close peripheral unit A10; When peripheral unit closing control circuit 4 is checked out slightly serious overcurrent situations, then can close peripheral unit A10 and peripheral unit B11 simultaneously; The rest may be inferred for all the other.When overcurrent situations heals when serious, peripheral unit closing control circuit 4 is just sent more shutdown signal and is closed more peripheral unit, so that reduce the electricity needs of total system.On the other hand, if peripheral unit closing control circuit 4 is to be realized by the circuit of (programming) able to programme (for example programmable micro controller), then the peripheral unit order of closing just can be determined by the user, the needs that this situation more can the compliance with system practical operation.
Following structure according to above-mentioned two kinds of different peripheral unit closing control circuits 4 describes embodiments of the present invention in detail.Be to be example explanation with notebook type (notebook) computer system in the following description, but this example is not in order to limiting the present invention, circuit structure of the following stated and control method go in other the electronic system too.
Fig. 2 represents to utilize in the present embodiment bleeder circuit and comparator circuit to realize detailed circuit diagram under peripheral unit closing control circuit 4 situations, that is implements peripheral unit closing control circuit 4 with fixing independent circuits.In structure shown in Figure 2, be to utilize the mode of closing electric fan, acoustic assembly, back light device and CDROM (compact disc read-only memory) to come the Adjustment System load current.As shown in the figure, power supply 1 sees through a supply path, and supply electric power is to laptop 1a, and current sensor 2 then is the load current that senses on the supply path of flowing through, and is converted into voltage form and is sent to amplifier 3.Amplifier 3 is made of resistor R 1, resistor R 2 and amplifier OP1, and gain (gain) is that the resistance value ratio by resistance R 1 and resistance R 2 decides.Amplifier 3 is sent load voltage value V0 at last.
In Fig. 2, peripheral unit closing control circuit 4 comprises bleeder circuit 5 (comprising resistor R 3, resistor R 4, resistor R 5, resistor R 6 and resistor R 7), comparer 6 (comprising operational amplifier OP2 and resistor R 10, R11), comparer 7 (comprising operational amplifier OP3 and resistance R 12, R13), comparer 8 (comprising operational amplifier OP4 and resistor R 14, R15) and comparer 9 (comprising operational amplifier OP5 and resistor R 16, R17).
Bleeder circuit 5 is to place between a load voltage value V0 and the end-point voltage (for example earth terminal GND), in order to produce a plurality of comparative voltages (V1, V2, V3, V4) between load voltage value V0 and end-point voltage.Each comparator circuit (6,7,8,9) then compares the comparative voltage (V1, V2, V3, V4) and the reference voltage (VR1, VR2, VR3, VR4) of correspondence respectively.In Fig. 2, each comparative voltage (V1, V2, V3, V4) is to be the relation that descends in regular turn, and corresponding to different excess current degree, the value of actual comparative voltage then is the resistance value decision by each resistor in the bleeder circuit 5.In addition, suppose that the resistor values ratio can obtain following relationship: VR1=VR2=VR3=VR4 for certain between the resistance of each comparator circuit (6,7,8,9).At this moment, each comparative voltage (V1, V2, V3, V4) promptly is equivalent to determine the excess current degree of load current in the comparison that each comparator circuit (6,7,8,9) is carried out, and uses the shutdown signal of generation corresponding to each peripheral unit.
Below determine the mode of each peripheral unit shutdown signal between explanation bleeder circuit 5 and each comparator circuit (6,7,8,9).Wherein, the degree of excess current is divided into and is that level Four, the first order are when branch pressure voltage V1＞reference voltage VR1 (the slightest excess current phenomenon); The second level is when branch pressure voltage V2＞reference voltage VR2; The third level is when branch pressure voltage V3＞reference voltage VR3; The fourth stage is when branch pressure voltage V4＞reference voltage VR4.This level Four excess current degree utilizes comparator circuit 6～9 to be judged respectively.In addition, when the condition of advanced number satisfied, the meaning work also can satisfy than the condition of harmonic series.
When the load current of load voltage value V0 representative does not reach the condition of excess current, that is each branch pressure voltage V1, V2, V3, V4 all be lower than reference voltage VR1 (=VR2=VR3=VR4) time, each peripheral unit (electric fan, sound module, back light device, CDROM) is all under normal operational circumstances.At this moment, the signal of high (H) level of comparator circuit 6 outputs makes transistor Q1 be conducting state, allows power supply VCC as the electric fan power supply.The signal of comparator circuit 7 output low (L) level, expression audible closure signal is for forbidding (disable) state.The signal of comparator circuit 8 output L level, when back of the body irradiation useful signal (being active low signal) was the L level, then OR logic gate G1 exported the back of the body irradiation control signal of L level.This back of the body irradiation control signal can see through the running of an inverter controlling back light device.Comparator circuit 9 is also exported the signal of L level, and when CDROM useful signal (being active low signal) was the L level, NOR logic gate G2 then exported the signal of H level to transistor Q2, makes its conducting, allows power supply VCC as the CDROM power supply.Therefore, each peripheral unit is in the state that can operate at this moment.
Then, when branch pressure voltage V1 is higher than reference voltage VR1, that is when satisfying the condition of first order excess current, comparator circuit 6 can be sent shutdown signal (L level) to transistor Q1, blocks the electric fan power supply so that close electric fan.When branch pressure voltage V2 is higher than reference voltage VR2, that is when satisfying the condition of second level excess current, comparator circuit 7 can be sent shutdown signal (H level), that is the audible closure signal, stops the running of acoustic assembly.At this moment, owing to first order overcurrent condition also meets, so electric fan also can shut down.When branch pressure voltage V3 is higher than reference voltage VR3, that is when satisfying the condition of third level excess current, comparator circuit 8 can be sent shutdown signal (H level) to OR logic gate G1, produces the back of the body irradiation control signal of H level, uses the running that stops back light device.At this moment, because the first order and second level overcurrent condition also meet, so electric fan also can shut down, acoustic assembly also can decommission simultaneously.When branch pressure voltage V4 is higher than reference voltage VR4, that is when satisfying the condition of fourth stage excess current, comparator circuit 9 can be sent shutdown signal (H level) to NOR logic gate G2, produces the signal of L level, make transistor Q2 be closed condition, by this stop supplies CDROM power supply.At this moment, because the first order, the second level and third level overcurrent condition also meet, so electric fan also can shut down, acoustic assembly and back light device also can decommission simultaneously.Therefore,, can adjust the load condition of the whole laptop 1a of system, just reduce load current and reach the purpose that anti-locking system is shut down suddenly according to different load current sizes.
Mainly be to utilize the branch pressure voltage of load voltage value V0 in Fig. 2, compare, judge the degree of excess current with a reference voltage through being produced after the dividing potential drop.When practical application, also can adopt other mode to carry out.For example, can utilize the bleeder circuit of cross-over connection between a reference voltage and an end-point voltage (GND), produce a plurality of between reference voltage and end-point voltage with reference to branch pressure voltage.Comparator circuit then will compare with reference to branch pressure voltage and load voltage value V0 respectively, with the excess current degree that decides load current, produce the shutdown signal corresponding to periphery.
As previously mentioned, except utilize fixing independent circuits realize peripheral unit closing control circuit 4, also can utilize programmable circuits such as microcontroller to be implemented.When utilizing microcontroller to realize peripheral unit closing control circuit 4, most importantly, determine each shutdown signal of required generation how according to load voltage value VO.Fig. 3 represents utilizing microcontroller to realize under the situation of peripheral unit closing control circuit 4 control flow chart of microcontroller in the present embodiment.At first, microcontroller receives the load voltage value V0 through amplifying, that is the pairing voltage form of load current (S1).Now compares load voltage value V0 and reference voltage level in regular turn according to load voltage value V0, so that judge the degree (S2) of excess current.As previously mentioned, judgment mode can utilize the load voltage value to produce each branch pressure voltage earlier, compares with a reference voltage, or utilizes a reference voltage to produce each dividing potential drop comparative voltage, compares with this load voltage value again.Then, then be to judge in regular turn whether each current condition satisfies.When the excess current degree exceeds in first order excess current standard (S3), at first send shutdown signal and close electric fan (S4).Now when the excess current degree exceeds in second level excess current standard (S5), is then further sent shutdown signal and is closed acoustic assembly (S6).Then, when the excess current degree exceeds in third level excess current standard (S7), then further send shutdown signal and close back light device (S8).When if the excess current degree reaches fourth stage excess current standard (S9), then send shutdown signal and close CD-ROM (S10).Therefore, according to different excess current degree, can close electric fan, acoustic assembly, back lighting device and CD-ROM in regular turn.In addition, because microcontroller is the programmable electronic element, therefore above-mentioned peripheral unit closing sequence can also be set by the user.
According to the above, the flow process that prevents the method for overcurrent from resulting in system stop of the present invention, as shown in Figure 4.At first, utilize current sensing element, the load current on the sensing supply path (S11) is converted to load current corresponding load voltage value (S12) again.Now, according to the load voltage value, the peripheral unit that determines the excess current degree and need close produces corresponding shutdown signal (S13).Utilize this shutdown signal at last, see through appropriate drive mode, close corresponding peripheral unit (S14).By this, system reach the excess current degree that is enough to shut down before, just can see through the action of closing peripheral unit, the reduction system prevents the situation of overcurrent from resulting in system stop by this for the demand of load electric.In addition, because the peripheral unit of being closed can't directly have influence on the running of system, so system still can remain under the environment of normal running and handles.
Though the present invention discloses as above with a preferred embodiment; but be not in order to limit the present invention; the people of any skilled can make and change and modification without departing from the spirit and scope of the present invention, so protection domain of the present invention is determined by the scope that appending claims defined.
Claims (12)
1. device that prevents overcurrent from resulting in system stop, this system comprises a plurality of peripheries of a core main control part, and sees through a supply path by a power supply electric power is provided, and it is characterized in that described device comprises:
One current sensing circuit near described supply path, in order to detecting the load current on the described supply path, and produces load voltage corresponding to this load current; And
One peripheral control circuit, be coupled to described current sensing circuit, it is according to the described load voltage value corresponding to described load current, judge the excess current degree of described load current, and excess current degree according to described load current, generation is used the described peripheral unit of closed portion corresponding to the shutdown signal of required device of closing in the periphery.
2. device as claimed in claim 1 is characterized in that described current sensing circuit comprises an amplifier, in order to amplify the described load voltage that described load current is changed.
3. device as claimed in claim 1 is characterized in that, described peripheral control circuit is a microcontroller.
4. device as claimed in claim 1 is characterized in that, described peripheral control circuit comprises:
One bleeder circuit, be coupled to described current sensing circuit and place described load voltage and an end-point voltage between, in order to produce a plurality of comparative voltages between described load voltage and described end-point voltage; And
A plurality of comparator circuits compare these comparative voltages and a reference voltage respectively, in order to determine the excess current degree of described load current, produce the shutdown signal corresponding to these peripheries.
5. device as claimed in claim 1 is characterized in that, described peripheral control circuit comprises:
One bleeder circuit is coupled between a reference voltage and the end-point voltage, in order to produce a plurality of with reference to branch pressure voltage between described reference voltage and described end-point voltage; And
A plurality of comparator circuits will compare with reference to branch pressure voltage and described load voltage respectively, in order to determine the excess current degree of described load current, produce the shutdown signal corresponding to these peripheries.
6. as claim 4 or 5 described devices, it is characterized in that described end-point voltage is an earth terminal voltage.
7. device as claimed in claim 1 is characterized in that, described system is a computer system, and these peripheries are followed successively by electric fan, acoustic assembly, back light device and CD player according to its order of closing.
8. method that prevents overcurrent from resulting in system stop, described system comprises a core main control part and a plurality of periphery, and sees through a supply path by a power supply electric power is provided, and it is characterized in that described method comprises the following steps:
The load current that is flow through on the described supply path of sensing;
Change described load current and be corresponding load voltage;
According to described load voltage with and the excess current degree of corresponding described load current, produce shutdown signal corresponding to required device of closing in these peripheries; And
Utilize described shutdown signal, close required device of closing in these peripheries.
9. method as claimed in claim 8 is characterized in that the step that produces described shutdown signal comprises the following steps:
Utilize a described load voltage and an end-point voltage, produce a plurality of comparative voltages between described load voltage and described end-point voltage;
Compare these comparative voltages and a reference voltage, to determine the excess current degree of described load current; And
According to the excess current degree of described load current, produce shutdown signal corresponding to required device of closing in these peripheries.
10. method as claimed in claim 8 is characterized in that the step that produces described shutdown signal comprises the following steps:
Utilize a reference voltage and an end-point voltage, produce a plurality of reference comparison voltages between described reference voltage and described end-point voltage;
Compare these reference comparison voltages and described load voltage, to determine the excess current degree of described load current; And
According to the excess current degree of described load current, produce shutdown signal corresponding to required device of closing in these peripheries.
11., it is characterized in that described end-point voltage is an earth terminal voltage as claim 9 or 10 described methods.
12. method as claimed in claim 8 is characterized in that, described system is a computer system, and these peripheries are followed successively by electric fan, acoustic assembly, back light device and CD player according to its order of closing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB001018108A CN1171134C (en) | 2000-01-25 | 2000-01-25 | Equipment and method of preventing overcurrent from resulting in system stop |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB001018108A CN1171134C (en) | 2000-01-25 | 2000-01-25 | Equipment and method of preventing overcurrent from resulting in system stop |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1307259A CN1307259A (en) | 2001-08-08 |
| CN1171134C true CN1171134C (en) | 2004-10-13 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB001018108A Expired - Fee Related CN1171134C (en) | 2000-01-25 | 2000-01-25 | Equipment and method of preventing overcurrent from resulting in system stop |
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| Country | Link |
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| CN (1) | CN1171134C (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7685451B2 (en) * | 2002-12-20 | 2010-03-23 | Intel Corporation | Method and apparatus to limit current-change induced voltage changes in a microcircuit |
| JP3711557B2 (en) * | 2003-08-21 | 2005-11-02 | オムロン株式会社 | Information processing apparatus and method, recording medium, and program |
| CN100347679C (en) * | 2004-07-16 | 2007-11-07 | 佛山市顺德区顺达电脑厂有限公司 | System power supply monitoring apparatus |
| CN101593014B (en) * | 2008-05-30 | 2012-09-19 | 华硕电脑股份有限公司 | Power supply management module and computer |
| TWI492036B (en) | 2008-05-30 | 2015-07-11 | Asustek Comp Inc | Power management system and computer thereof |
| CN105305367B (en) * | 2014-05-30 | 2018-05-15 | 宇龙计算机通信科技(深圳)有限公司 | A kind of over-current protection method and system |
| CN106487092B (en) * | 2016-11-28 | 2019-02-05 | 国网山东省电力公司济宁供电公司 | Low pressure electricity consumption line facility protects system and method |
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2000
- 2000-01-25 CN CNB001018108A patent/CN1171134C/en not_active Expired - Fee Related
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| Publication number | Publication date |
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| CN1307259A (en) | 2001-08-08 |
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